code: def revise_unanswerable(preds, na_probs, na_prob_thresh):
      """
      Revise the predictions results and return a null string for unanswerable question
      whose unanswerable probability above the threshold.
  
      Parameters
      ----------
      preds: dict
          A dictionary of full prediction of spans
      na_probs: dict
          A dictionary of unanswerable probabilities
      na_prob_thresh: float
          threshold of the unanswerable probability
  
      Returns
      -------
      revised: dict
          A dictionary of revised prediction
      """
      revised = copy.deepcopy(preds)
      for q_id in na_probs.keys():
          if na_probs[q_id] > na_prob_thresh:
              revised[q_id] = ""
      return revised
  
file_path: gluon-nlp/docs/model_zoo/question_answering/eval_utils.py
imports: import collections
  import json
  import copy
  import re
  import string
label_desc: Use image node_id 12 for calling a global function with example usage: revise_unanswerable(preds, na_probs, na_prob_thresh) and returns: revised